Blast furnace bell



Sept. 27, 1966 R. T. HANNA BLAST FURNACE BELL 2 Sheets-Sheet l FiledDec.

l/VVENTOR. RALPH 7: HAN/VA Attorney Sept. 27, 1966 R. T. HANNA BLASTFURNACE BELL 2 Sheets-Sheet 2 Filed Dec.

INVENTOR. RALPH 7. HANNA W Arforney United States Patent 3,275,310 BLASTFURNACE BELL Ralph T. Hanna, Yardley, Pa., assignor to United StatesSteel Corporation, a corporation of Delaware Filed Dec. 4, 1963, Ser.No. 327,925 2 Claims. (Cl. 266-27) This invention relates to a blastfurnace bell and more particularly to the small bell for an ironproducing blast furnace. In order to charge the blast furnace, the .topof the furnace is provided with a double bell arrangement having anupper or small bell which provides a seal between .a revolving hopperand the lower ball hopper. In charging, the materials are dumped by askip onto the small bell after which the small bell is moved downward-1y to drop the material onto the large bell. Afiter a number of skiploads the large bell is opened and the small bell held closed and thematerial dropped into the furnace. When the large bell is in its loweror open position the small bell must provide a tight seal between thepressure of the furnace and the atmosphere. Since the materials of thecharge are highly abrasive the small bell wears rapidly as the materialslides over its outer surface. After a period of between 12 and 18months the sealing surface of the small bell is worn to such an extentthat the bell must be replaced. The rod sup porting the large bellpasses through the hollow rod which supports the small bell so that thesmall bell is made in two pieces with the two halves split in a verticalplane. A wearing apron is generally provided around the top of the smallbell and the bottom of its rod and wearing rings are provided above thewearing apron around the small bell rod. In order to replace the bell,the wearing rings and apron are raised to clear the bell and the boltsholding the two halves of the bell together are unbolted from beneath.The bell is then removed from the rod and dropped down into the spacebetween the bells where they are removed from the furnace through a manhole. Because of the diflicult working conditions and because thewearing rings and apron tend to stick together so that they aredifficult to raise, it is necessary to shut the furnace down for aperiod of between 16 to 24 hours each time the bell is replaced.

It is therefore an object of my invention to provide a small hell thatis so constructed that only a portion thereof need be replaced.

Another object is to provide such a bell which is so constructed thatthe time necessary to renew it is greatly reduced.

These and other objects will be more apparent after referring to thefollowing specification and attached drawings, in which:

FIGURE 1 is an elevation, partly in section, showing the small bell ofmy invention in place on a blast furnace;

FIGURE 2 is an elevation showing one half of the bell of my invention;and

FIGURE 3 is a view taken on the line IIIIII of FIG- URE 2.

Referring more particularly to the drawings, reference numeral 2indicates a hopper having a peripheral conical seat 4 at the lower endthereof, A hollow rod 6 extends downwardly through the hopper 2 and hasa small bell =8 attached thereto in the usual manner. The top of the rod6 is supported by support assembly 10 which is attached to the usuallifting mechanism 11, only a part of which is shown. A large bell rod 12extends downwardly through hollow rod 6 to the large bell, not shown. Awearing apron 14 surrounds the top of the bell 8 and the bott-omof therod 6. Wearing rings 16 are provided around the rod 6 above the apron14. The parts so far Patented Sept. 27, 1966 "ice described, except forthe construction of bell 8, are conventional.

According to my invention the hell 8 is made up of four generally hollowconical sections 18, 20, 22 and 24. The upper sections 18 and 20 eachhas an inwardly extending generally vertical flange 26 on each end withmatching aligned holes therein so that they can be fastened together bymeans of bolts 28. A vertical shoulder 30 is provided around the loweroutside periphery of the sections 18 and 20. The lower sections 22 and24 each has an inwardly extending horizontal flange 32 at the topthereof and the upper sections 18 and 20 each has -a correspondinghorizontal flange 34 at its lower end which abuts the flanges 32.Aligned holes are provided in the flanges '32 and 34 for receiving bolts36. The sections 22 and 24 each has an inwardly extending verticalflange 38 at each end having aligned holes 40 therein for receivin bolts42.

A generally conical sealing surface 44 is provided around the peripheryof the sections 22 and 24 for engagement with the seat 4.

When the sealing surfaces 44 become worn to such an extent thatexcessive gas leakage occurs, the furnace is shut down with the largebell closing the top thereof below the small hell 8. The workmen enterthe space between the bells through a man hole, not shown, and removethe bolts 36 and 42 thus separating the sections 22 and 24 from eachother and from sections 18 and 20. Since the sections 22 and 24 arerelatively small they need not be removed but can be placed on the largebell and later dumped into the blast furnace. New sections 22 and 24 arethen assembled together and to the sections 18 and 20 by means of bolts36 and 42. I have found that this replacement can be accomplished muchfaster than the replacement of the bells previously used so that thedown time of the furnace is about 6 hours. If desired the upper sections18 and 20 can be made thicker than usual without their weight beingincreased to such an extent that they cannot be readily handled. Thispermits elimination of the wearing apron. By providing the shoulder 30less wear occurs on the sealing surfaces 44 since the material slidingdown over the bell will tend to slide from the outer surfaces of thesections 18 and 20 directly to the large bell hopper.

While one embodiment of my invention has been shown and described, itwill be apparent that other adaptations and modifications may be madewithout departing from the scope of the following claims:

I claim:

1. In a blast furnace, the combination including a hopper having aperipheral conical seat at its lower end, a generally conical bellwithin said hopper and extending below the bottom thereof, and means forraising and lowering said bell; said bell comprising two upper sectionshaving a generally conical outer surface, a generally vertical flange oneach end of each upper section, the flanges on each section having holestherein aligned with the holes in the adjacent flange of the othersection, means in said aligned holes detachably fastening the twosections together, two lower sections having a generally conical outersealing surface adapted to engage said peripheral conical seat, agenerally vertical flange on each end of each lower section, the flangeson each lower section having holes therein aligned with the holes in theadjacent flange of the other lower section, means in said last namedaligned holes detachably fastening the lower sections together, each ofsaid upper sections having an inwardly extending peripheral flange .atthe bottom thereof, each of said lower sections having an inwardlyextending peripheral flange at the top thereof, said horizontal flangeshaving holes therein, the holes in the horizontal flanges of the uppersections being aligned with 3 4 the holes in the horizontal flanges ofthe lower sections, References Cited by the Examiner glsdeggeanihin saidlistdnameed aligtngdsh tcglggt 1ileltaeh'a-bly UNITED STATES PATENTSng-eupper n owrsecin 2. The combination of claim 1 in which [the outersur- 2,429,481 10/1947 Mohr et 266-47 face of the bell includes .auniform diameter portion ad- 5 jacent the junction between the upper andlower section-s JOHN CAMPBELL P'lmary Examiner with the maximum diameterof the joined upper sections M. L. FAIGUS, Assistanl Examiner.

and the minimum diameter of the joined lower sections being equal tosaid uniform diameter portion.

1. IN A BLAST FURNACE, THE COMBINATION INCLUDING A HOPPER HAVING APERIPHERAL CONICAL SEAT AT ITS LOWER END, A GENERALLY CONICAL BELLWITHIN SAID HOPPER AND EXTENDING BELOW THE BOTTOM THEREOF, AND MEANS FORRAISING AND LOWERING SAID BELL; SAID BELL COMPRISING TWO UPPER SECTIONSHAVING A GENERALLY CONICAL OUTER SURFACE, A GENERALLY VERTICAL FLANGE ONEACH END OF EACH UPPER SECTION, THE FLANGES ON EACH SECTION HAVING HOLESTHEREIN ALIGNED WITH THE HOLES IN THE ADJACENT FLANGE OF THE OTHERSECTION, MEANS IN SAID ALIGNED HOLES DETACHABLY FASTENING THE TWOSECTIONS TOGETHER, TWO LOWER SECTIONS HAVING A GENERALLY CONICAL OUTERSEALING SURFACE ADAPTED TO ENGAGE SAID PERIPHERAL CONICAL SEAT, AGENERALLY VERTICAL FLANGE ON EACH END OF EACH LOWER SECTION, THE FLANGESON EACH LOWER SECTION HAVING HOLES THEREIN ALIGNED WITH THE HOLES IN THEADJACENT FLANGE OF THE OTHER LOWER SECTION, MEANS IN SAID LAST NAMEDALIGNED HOLES DETACHABLY FASTENING THE LOWER SECTIONS TOGETHER, EACH OFSAID UPPER SECTIONS HAVING AN INWARDLY EXTENDING PERIPHERAL FLANGE ATTHE BOTTOM THEREOF, EACH OF SAID LOWER SECTIONS HAVING AN INWARDLYEXTENDING PERIPHERAL FLANGE AT THE TOP THEREOF, SAID HORIZONTAL FLANGESHAVING HOLES THEREIN, THE HOLES IN THE HORIZONTAL FLANGES OF THE UPPERSECTIONS BEING ALIGNED WITH THE HOLES IN THE HORIZONTAL FLANGES OF THELOWER SECTIONS, AND MEANS IN SAID LAST NAMED ALIGNED HOLES DETACHABLYFASTENING THE UPPER AND LOWER SECTIONS TOGETHER.